Mixed Definition and 251 Threads

I've already calculated the total spin of the system in the addition basis: ##\ket{1 \frac{3}{2} \frac{3}{2}}; \ket{1 \frac{3}{2} \frac{-3}{2}}; \ket{1 \frac{3}{2} \frac{1}{2}}; \ket{1 \frac{3}{2} \frac{-3}{2}}; \ket{0 \frac{1}{2} \frac{1}{2}}; \ket{0 \frac{1}{2} \frac{-1}{2}}; \ket{1...

A company has made a skin peel made with 33% tca 5% kojic acid and 62% hydrogen peroxide. But you don’t peel. I want to make my own since I can’t afford the product. How do I do it

The whole problem arouse because there's no authentic local source. One thing that I need to learn is are these both same thing? Or are different? Is combined LCG also LCG or anything can be called combined method? Even our teachers aren't very sure of it(as they were not the ones who designed...

I have a source that says when two particles are entangled, we must describe them using the density operator because it is a mixed state. But I have another source that says that the singlet state of two spins is an entangled state, but that has a wavefunction. So could someone explain what I am...

I have some basic questions about mixed states and entanglement. 1. Do mixed states always imply that the states are entangled and vice versa? 2. Can mixed states ever be separable? 3. Does interference have anything to do with entanglement? In terms of Density Matrices, ρ = |ψ><ψ|: 4...

Considering SG experiment, it is usually described as if an atom in the end of its path (but before being detected on the screen) is in the superposition state, say, ##|\textsf{spin up}, \textsf{upper path}\rangle+|\textsf{spin down}, \textsf{lower path}\rangle##. Some books (Feynman lectures...

I got (a) and (b) but I'm still working on (c). The solutions can be found here for your reference: https://ocw.mit.edu/courses/electrical-engineering-and-computer-science/6-041sc-probabilistic-systems-analysis-and-applied-probability-fall-2013/unit-ii/lecture-9/MIT6_041SCF13_assn05_sol.pdf. But...

I'm an undergrad in physics, and have been asking myself the following question recently. Suppose you have a pure quantum state p (von neumann entropy=0), made of 2 sub-states p1 and p2 that are entangled. Because they are entangled, p \neq p1 x p2. Hence the entanglement entropy of p (=0) is...

How do you prove Heisenberg uncertainty relations for mixed states (density matrix), only from knowing the relation is true for pure states?

Wood Magazine https://www.woodmagazine.com/materials-guide/finishes/get-the-color-out-with-wood-bleach descibes the chemistry of two-part wood bleaches as follows: Since they neutralize each other, why are the two parts mixed before being applied to wood?

I use the operator method here: (D^2 + D+3)y = 5cos(2x+3) ## y = \frac{1}{D^2+D+3} 5cos(2x+3) ## ## \Rightarrow y= \frac{5}{-(2)^2+D+3}cos(2x+3) ## ## \Rightarrow y= \frac{5}{-4+D+3}cos(2x+3) ## ## \Rightarrow y= \frac{5}{D-1}cos(2x+3) ## At this, if I revert back to write: (D-1)y = 5cos(2x+3)...

I have the solution, but my question is that in my first attempt, I simply calculated a_c = 60^2/150 ignoring the fact that the units for 60 are km/hr and the units for 150 are meters. Is this ever salvageable? Is there any way to retain the 'mixed' units of km with meters in the ratio and...

Is this anyhow possible ? The system would be a wave equation modelized by a finite elements basis in space and time. Is there any method to do the limit discretization->continuum with paper and pencil ?

the entropy change for a reversible adiabatic process is zero as it remains constant. Is this a reversible process? assuming T1>T2: hot (h) water has mass M, temp T1 cold (c) water has mass nM, temp T2 let the final temperature be Tf if δQ=0 as the process is adiabatic, |Qh|=|Qc| so Qh=-Qc...

Hello, Anybody have any good sources of mixed up old electrical components? For example: an old drawer full of mixed up resistors and capacitors; wax caps and jumbled up stuff? I have a HUGE jar that I am trying to fill up with this type of thing for my lab and was just wondering if anybody...

This is a meta-analysis. It looks at data sets from other studies. https://annals.org/aim/article-abstract/2737825/effects-nutritional-supplements-dietary-interventions-cardiovascular-outcomes-umbrella-review-evidence For cardiovascular diseases and stroke: this paper shows that interventions...

Well, I have no clues for this problem. Since I can get nothing from the definition of ##\rho##, I tried from the right part. Also, I know that ##\left ( \vec r \cdot \vec \sigma \right ) ^2={r_1}^2 {\sigma _1}^2+{r_2}^2 {\sigma _2}^2+{r_3}^2 {\sigma _3}^2##. Plus, ##\rho## is positive; then...

Considering a mixture ##\sum p_i|\Psi_i\rangle\langle\Psi_i|## This does not describe an ensemble of quantum systems since the particle number is defined by ##\Psi_i##. The question is in the continuous wave-mechanical formalism where I don't understand what object the density matrix is : I...

Could it be possible that using a mixed stated ##\rho=\sum_{i=1}^4|\langle e_i|\Psi\rangle|^2|e_i\rangle\langle e_i|## Where ##\Psi## is the singlet state and the ##e_i## form an orthonormal basis (like an intermediary state),That one could violate Tsirelson's bound if the parameters describing...

Hi all. So is anyone having any luck with sw. power PCB mount supply modules for mixed signal? I have been experimenting with little DC-DC +5, +-15 and the TDK-Lambda AC/+5/+-15 power module. I have a mixed signal design that has a small size and low weight factor in my design. I have about...

Being scratching my head for 2 days and not getting anywhere with this one. I am trying to figure out how to perform a 3D rotation described via a mix of intrinsic and extrinsic angles. Here is the problem: I have a platform in the shape of a box with sides of length lx, ly and lz. The platform...

Homework Statement Give your own example of a statement with two different quantifiers which changes its meaning and truth value when the order of the quantifiers is exchanged. Homework EquationsThe Attempt at a Solution (∀x∈ℝ)(∃x∈ℝ)(xy=0) is true but (∃x∈ℝ)(∀x∈ℝ)(xy=0) is false. Is this...

Homework Statement The following circuit is given, and all voltage, current, resistance and power must be found for each resistor. I have found the following information: Vsrc = ? Isrc = .5A Rsrc = ? Psrc = ? V1 = ? I1 = .5A R1 = ? P1 = ? V2 = 2.5V I2 = .25A R2 = 10 P2 = .625W V3 =...

Hello, If I have a homgeneous linear differential equation like this one (or any other eq): $$y''(x)-y'(x)=0$$ And they give me these Dirichlet boundary conditions: $$y(0)=y(1)=0$$ Can I transform them into a mixed boundary conditions?: $$y(0)=y'(1)=0$$ I tried solving the equation, derivating...

hey! EDIT: I didn’t post this in homework help because there aren’t any computational questions, it’s just conceptual My assignment scenario consists of a star (blackbody) surrounded by an expanding shell of hot gas. I’m given its spectrum and it is a continuous emission spectrum. Emission...

Imagine a two-state system, e.g., a single nucleus that can be aligned or anti-aligned with an external magnetic field. If that nucleus is in a "mixed state" at time zero, such that it's wavefunction is 50% up and 50% down at time zero, why can that nucleus absorb a "quanta" of radiofrequency...

Ok so I don't know what is wrong with me, but when it comes to graphs I often get x and y mixed up and the whole thing becomes very confusing. I had this question plot a graph using y = 2/3x The answer is: if x = 3 y = (2/3 * 3) = 2 x = 3, y = 2 and these are integers which can be plotted...

Homework Statement A beam of neutrons (moving along the z-direction) consists of an incoherent superposition of two beams that were initially all polarized along the x- and y-direction, respectively. Using the Pauli spin matrices: \sigma_x = \begin{pmatrix} 0 & 1 \\ 1 & 0 \\...

Why is entropy lost by hot water less than the entropy gained by the cold water?From perspective of energy,why is it better to take water and heat it to a temperature than it is to mix hot water and cold water to get a particular temperature.

Homework Statement How to find mass of one of the two liquids being mixed if we know all other variables in this formula T = ( m1c1T1 + m2c2T2 ) / ( m1c1 + m2c2 ) ? Homework Equations T = ( m1c1T1 + m2c2T2 ) / ( m1c1 + m2c2 ) The Attempt at a Solution

A pure state can be interpreted as belonging to a system, but it can also be interpreted as belonging to a single particle (although the resulting probability is in respect to the system), and as I understand it, this is now the preferred interpretation. But in...

Hello everybody. I am trying to understand better what happens at a liquid-gas phase transition for the Van Der Waals model. From what I have understood, from the Van Der Waals model we are able to plot the curve P(V) and to calculate the free energy F. Here are such curves : Then, we...

Homework Statement See attached image (See below) Homework Equations Differential equations. And a combination of discrete & continuous distributions The Attempt at a Solution The Continous Distribution Function (CDF) is given in the question. So I differentiated it with respect to x...

Hi I am to calculate Rab of the circuit and I have no idea on how to approach this problem. It would have been all nice and eaasy if it weren't for the vertival 30 ohm resistor. Because of this I'm in a dark spot. I will appreciate any help.

Hi. 1. Does a pure state belong to mixed states \hat{\rho}=\sum_k p_k|\psi_k><\psi_k| where ##p_k=1## for k=i and otherwise 0 ? 2. Does quantum jump by observation work for both mixed and pure states ? Your teachings will be appreciated.

Hello guys, I am trying to understand the following experiment: 1. Prepare a 2 level atom in state |0> 2. Shine in a Pi/2 pulse --> atom goes to 1/√2 (|0>+|1>) 3. Wait time T 4. Shine in second Pi/2 pulse a) if the state is pure: atom will go to state |1>, p1=1 b) if the state is...

According to decoherance. Say there is a pure state initially in state: |ψ⟩=α|0⟩+β|1⟩ After decoherance (interaction with environment), the system will transform into the improper mixed state of: ρ=|α|2|0⟩⟨0|+|β|2|1⟩⟨1| This is the "apparent" collapse that decoherance refers to. With the...

A mixed state is when the system is actually in one state or another, but you just don't know which, and you use probabilities to describe your uncertainty. I'm referring to a mixed state of the entire system. I want an actual example. Can you think of some? Note I wasn't describing mixed state...

Hey guys, I am having issues with understanding the physical nature of pure and mixed states. Maybe you can help me out? 1) A pure state - superposition is a state that consists of different states at the same time. It's like having several waves, each one belonging to an Eigenstate of the...

I just want to be sure I understand this correctly: Suppose there's a long spaceship moving in uniform motion relative to me (an inertial frame). Now someone in the front* of the spaceship calls someone (on the phone) in the back of the spaceship. *(this long length of the ship is oriented...

Homework Statement Find dy of ##~xy^2+x^2y=4## Homework Equations Differential of a product: $$d(uv)=u\cdot dv+v\cdot du$$ The Attempt at a Solution $$2xy~dy+y^2~dx+x^2~dy+2xy~dx=0$$ $$x(2y+x)dy=-(y+2x)dx$$

Homework Statement If a metal is adhered to a surface of another metal, let's say copper is plated onto aluminum, how can the elastic modulus of copper can be extracted given only the data of the thickness of the copper and aluminum, the young's modulus of the combined metal and the modulus of...

I'm trying to solve a problem where I am given a few matrices and asked to determine if they could be density matrices or not and if they are if they represent pure or mixed ensembles. In the case of mixed ensembles, I should find a decomposition in terms of a sum of pure ensembles. The matrix...

Hi, I'm new. Please bear with me because I'm not familiar with the code of this forum. I don't know how to enter a mixed fraction correctly, so I'm just going to write it out. Here is the problem: Four and five-ninths minus 2/3 Can someone explain to me why the answer is three and...

What are the coordinates on the 3D Bloch ball of a qubit's mixed state of the form: ##\rho=p_{00}|0\rangle \langle 0|+p_{01}|0\rangle \langle 1|+p_{10}|1\rangle \langle 0|+p_{11}|1\rangle \langle 1|##

I have actually read so much about density matrix and eigenstates today. I just want to know what particular situations when mixed states are eigenstates. Can this occur? Mixed states and eigenstates have one thing in common.. they have a value.. but I know mixed states aren't eigenstates...

Hello, sorry, I do realize that this question has been asked before but there are just a few things I would like to figure out. So, in my mind the differences lie in knowing the states that the system could end up in, and also the difference in the probabilities. Is this thinking correct...

Is it in a Quantum superposition, and then only in a mixed state when finding the reduced state of a qubit from an entanglement of multiple qubits?

If you have a density matrix \rho, there is a basis |\psi_j\rangle such that \rho is diagonal in that basis. What are the conditions on \rho such that the basis that diagonalizes it is unique? It's easy enough to work out the answer in the simplest case, of a two-dimensional basis: Then \rho...

Is that true in general and why: $$A^{mn}_{.~.~lm}=A^{nm}_{.~.~ml}$$